[lxc-devel] [PATCH] lxc api: fix some config_path oddities

Stéphane Graber stgraber at ubuntu.com
Mon Feb 11 04:22:37 UTC 2013


On 02/08/2013 05:06 PM, Serge Hallyn wrote:
> 1. When calling c->set_config_path(), update configfile.  I.e. if we
> are setting the config_path to /var/lib/lxc, then the configfile should
> be changed to /var/lib/lxc/$container/config
> 
> 2. Add an optional configpath argument to lxc_container_new.  If NULL,
> then the default will be used (as before).  If set, then the passed-in
> path will be used.  This way you can do
> 
> 	c1 = lxc.Container("r1", "/var/lib/lxc");
> 	c2 = lxc.Container("r2", "/home/user/lxcbase");
> 
> (Note I did *not* implement the python or lua binding to pass that
> argument along)
> 
> Signed-off-by: Serge Hallyn <serge.hallyn at ubuntu.com>

Acked-by: Stéphane Graber <stgraber at ubuntu.com>

I'll update the python binding tomorrow to export the new option of the
constructor.

> ---
>  src/lua-lxc/core.c         |  2 +-
>  src/lxc/lxc.h              |  2 +-
>  src/lxc/lxccontainer.c     | 72 ++++++++++++++++++++++++++++++++-------
>  src/lxc/lxccontainer.h     |  2 +-
>  src/python-lxc/lxc.c       |  2 +-
>  src/tests/Makefile.am      |  3 +-
>  src/tests/containertests.c |  4 +--
>  src/tests/createtest.c     |  2 +-
>  src/tests/destroytest.c    |  2 +-
>  src/tests/get_item.c       |  8 ++---
>  src/tests/getkeys.c        |  2 +-
>  src/tests/lxcpath.c        | 85 ++++++++++++++++++++++++++++++++++++++++++++++
>  src/tests/saveconfig.c     |  2 +-
>  src/tests/shutdowntest.c   |  2 +-
>  src/tests/startone.c       |  2 +-
>  15 files changed, 162 insertions(+), 30 deletions(-)
>  create mode 100644 src/tests/lxcpath.c
> 
> diff --git a/src/lua-lxc/core.c b/src/lua-lxc/core.c
> index ae4d9b2..9225158 100644
> --- a/src/lua-lxc/core.c
> +++ b/src/lua-lxc/core.c
> @@ -44,7 +44,7 @@
>  static int container_new(lua_State *L)
>  {
>      const char *name = luaL_checkstring(L, 1);
> -    struct lxc_container *c = lxc_container_new(name);
> +    struct lxc_container *c = lxc_container_new(name, NULL);
>  
>      if (c) {
>  	lua_boxpointer(L, c);
> diff --git a/src/lxc/lxc.h b/src/lxc/lxc.h
> index 349bbbc..a651d04 100644
> --- a/src/lxc/lxc.h
> +++ b/src/lxc/lxc.h
> @@ -182,7 +182,7 @@ extern const char const *lxc_version(void);
>  /*
>   * Create and return a new lxccontainer struct.
>   */
> -extern struct lxc_container *lxc_container_new(const char *name);
> +extern struct lxc_container *lxc_container_new(const char *name, const char *configpath);
>  
>  /*
>   * Returns 1 on success, 0 on failure.
> diff --git a/src/lxc/lxccontainer.c b/src/lxc/lxccontainer.c
> index 6f01645..733cbb6 100644
> --- a/src/lxc/lxccontainer.c
> +++ b/src/lxc/lxccontainer.c
> @@ -871,10 +871,45 @@ static const char *lxcapi_get_config_path(struct lxc_container *c)
>  	return (const char *)(c->config_path);
>  }
>  
> +/*
> + * not for export
> + * Just recalculate the c->configfile based on the
> + * c->config_path, which must be set.
> + * The lxc_container must be locked or not yet public.
> + */
> +static bool set_config_filename(struct lxc_container *c)
> +{
> +	char *newpath;
> +	int len, ret;
> +
> +	if (!c->config_path)
> +		return false;
> +
> +	/* $lxc_path + "/" + c->name + "/" + "config" + '\0' */
> +	len = strlen(c->config_path) + strlen(c->name) + strlen("config") + 3;
> +	newpath = malloc(len);
> +	if (!newpath)
> +		return false;
> +
> +	ret = snprintf(newpath, len, "%s/%s/config", c->config_path, c->name);
> +	if (ret < 0 || ret >= len) {
> +		fprintf(stderr, "Error printing out config file name\n");
> +		free(newpath);
> +		return false;
> +	}
> +
> +	if (c->configfile)
> +		free(c->configfile);
> +	c->configfile = newpath;
> +
> +	return true;
> +}
> +
>  static bool lxcapi_set_config_path(struct lxc_container *c, const char *path)
>  {
>  	char *p;
>  	bool b = false;
> +	char *oldpath = NULL;
>  
>  	if (!c)
>  		return b;
> @@ -883,13 +918,28 @@ static bool lxcapi_set_config_path(struct lxc_container *c, const char *path)
>  		return b;
>  
>  	p = strdup(path);
> -	if (!p)
> +	if (!p) {
> +		ERROR("Out of memory setting new lxc path");
>  		goto err;
> +	}
> +
>  	b = true;
>  	if (c->config_path)
> -		free(c->config_path);
> +		oldpath = c->config_path;
>  	c->config_path = p;
> +
> +	/* Since we've changed the config path, we have to change the
> +	 * config file name too */
> +	if (!set_config_filename(c)) {
> +		ERROR("Out of memory setting new config filename");
> +		b = false;
> +		free(c->config_path);
> +		c->config_path = oldpath;
> +		oldpath = NULL;
> +	}
>  err:
> +	if (oldpath)
> +		free(oldpath);
>  	lxcunlock(c->privlock);
>  	return b;
>  }
> @@ -938,10 +988,9 @@ out:
>  }
>  
>  
> -struct lxc_container *lxc_container_new(const char *name)
> +struct lxc_container *lxc_container_new(const char *name, const char *configpath)
>  {
>  	struct lxc_container *c;
> -	int ret, len;
>  
>  	c = malloc(sizeof(*c));
>  	if (!c) {
> @@ -950,7 +999,11 @@ struct lxc_container *lxc_container_new(const char *name)
>  	}
>  	memset(c, 0, sizeof(*c));
>  
> -	c->config_path = default_lxc_path();
> +	if (configpath)
> +		c->config_path = strdup(configpath);
> +	else
> +		c->config_path = default_lxc_path();
> +
>  	if (!c->config_path) {
>  		fprintf(stderr, "Out of memory");
>  		goto err;
> @@ -976,17 +1029,10 @@ struct lxc_container *lxc_container_new(const char *name)
>  		goto err;
>  	}
>  
> -	len = strlen(c->config_path)+strlen(c->name)+strlen("/config")+2;
> -	c->configfile = malloc(len);
> -	if (!c->configfile) {
> +	if (!set_config_filename(c)) {
>  		fprintf(stderr, "Error allocating config file pathname\n");
>  		goto err;
>  	}
> -	ret = snprintf(c->configfile, len, "%s/%s/config", c->config_path, c->name);
> -	if (ret < 0 || ret >= len) {
> -		fprintf(stderr, "Error printing out config file name\n");
> -		goto err;
> -	}
>  
>  	if (file_exists(c->configfile))
>  		lxcapi_load_config(c, NULL);
> diff --git a/src/lxc/lxccontainer.h b/src/lxc/lxccontainer.h
> index 32c501e..de802a8 100644
> --- a/src/lxc/lxccontainer.h
> +++ b/src/lxc/lxccontainer.h
> @@ -82,7 +82,7 @@ struct lxc_container {
>  #endif
>  };
>  
> -struct lxc_container *lxc_container_new(const char *name);
> +struct lxc_container *lxc_container_new(const char *name, const char *configpath);
>  int lxc_container_get(struct lxc_container *c);
>  int lxc_container_put(struct lxc_container *c);
>  int lxc_get_wait_states(const char **states);
> diff --git a/src/python-lxc/lxc.c b/src/python-lxc/lxc.c
> index 83e2659..16356f9 100644
> --- a/src/python-lxc/lxc.c
> +++ b/src/python-lxc/lxc.c
> @@ -85,7 +85,7 @@ Container_init(Container *self, PyObject *args, PyObject *kwds)
>                                        &name))
>          return -1;
>  
> -    self->container = lxc_container_new(name);
> +    self->container = lxc_container_new(name, NULL);
>      if (!self->container) {
>          fprintf(stderr, "%d: error creating lxc_container %s\n", __LINE__, name);
>          return -1;
> diff --git a/src/tests/Makefile.am b/src/tests/Makefile.am
> index 5850727..a883d36 100644
> --- a/src/tests/Makefile.am
> +++ b/src/tests/Makefile.am
> @@ -15,6 +15,7 @@ lxc_test_createtest_SOURCES = createtest.c
>  lxc_test_shutdowntest_SOURCES = shutdowntest.c
>  lxc_test_get_item_SOURCES = get_item.c
>  lxc_test_getkeys_SOURCES = getkeys.c
> +lxc_test_lxcpath_SOURCES = lxcpath.c
>  
>  AM_CFLAGS=-I$(top_srcdir)/src \
>  	-DLXCROOTFSMOUNT=\"$(LXCROOTFSMOUNT)\" \
> @@ -24,6 +25,6 @@ AM_CFLAGS=-I$(top_srcdir)/src \
>  
>  bin_PROGRAMS = lxc-test-containertests lxc-test-locktests lxc-test-startone \
>  	lxc-test-destroytest lxc-test-saveconfig lxc-test-createtest \
> -	lxc-test-shutdowntest lxc-test-get_item lxc-test-getkeys
> +	lxc-test-shutdowntest lxc-test-get_item lxc-test-getkeys lxc-test-lxcpath
>  
>  endif
> diff --git a/src/tests/containertests.c b/src/tests/containertests.c
> index d68f17c..8868faa 100644
> --- a/src/tests/containertests.c
> +++ b/src/tests/containertests.c
> @@ -103,7 +103,7 @@ int main(int argc, char *argv[])
>  
>  	ret = 1;
>  	/* test refcounting */
> -	c = lxc_container_new(MYNAME);
> +	c = lxc_container_new(MYNAME, NULL);
>  	if (!c) {
>  		fprintf(stderr, "%d: error creating lxc_container %s\n", __LINE__, MYNAME);
>  		goto out;
> @@ -149,7 +149,7 @@ int main(int argc, char *argv[])
>  	}
>  
>  	/* test a real container */
> -	c = lxc_container_new(MYNAME);
> +	c = lxc_container_new(MYNAME, NULL);
>  	if (!c) {
>  		fprintf(stderr, "%d: error creating lxc_container %s\n", __LINE__, MYNAME);
>  		ret = 1;
> diff --git a/src/tests/createtest.c b/src/tests/createtest.c
> index 48ce922..c2abee2 100644
> --- a/src/tests/createtest.c
> +++ b/src/tests/createtest.c
> @@ -33,7 +33,7 @@ int main(int argc, char *argv[])
>  	struct lxc_container *c;
>  	int ret = 1;
>  
> -	if ((c = lxc_container_new(MYNAME)) == NULL) {
> +	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
>  		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
>  		ret = 1;
>  		goto out;
> diff --git a/src/tests/destroytest.c b/src/tests/destroytest.c
> index 28f0577..0552b4c 100644
> --- a/src/tests/destroytest.c
> +++ b/src/tests/destroytest.c
> @@ -65,7 +65,7 @@ int main(int argc, char *argv[])
>  	struct lxc_container *c;
>  	int ret = 1;
>  
> -	if ((c = lxc_container_new(MYNAME)) == NULL) {
> +	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
>  		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
>  		ret = 1;
>  		goto out;
> diff --git a/src/tests/get_item.c b/src/tests/get_item.c
> index 0d32eca..d3e6d29 100644
> --- a/src/tests/get_item.c
> +++ b/src/tests/get_item.c
> @@ -35,7 +35,7 @@ int main(int argc, char *argv[])
>  	int ret;
>  	char v1[2], v2[256], v3[2048];
>  
> -	if ((c = lxc_container_new("testxyz")) == NULL) {
> +	if ((c = lxc_container_new("testxyz", NULL)) == NULL) {
>  		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
>  		ret = 1;
>  		goto out;
> @@ -157,7 +157,7 @@ int main(int argc, char *argv[])
>  	lxc_container_put(c);
>  
>  	// new test with real container
> -	if ((c = lxc_container_new(MYNAME)) == NULL) {
> +	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
>  		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
>  		ret = 1;
>  		goto out;
> @@ -165,7 +165,7 @@ int main(int argc, char *argv[])
>  	c->destroy(c);
>  	lxc_container_put(c);
>  
> -	if ((c = lxc_container_new(MYNAME)) == NULL) {
> +	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
>  		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
>  		ret = 1;
>  		goto out;
> @@ -179,7 +179,7 @@ int main(int argc, char *argv[])
>  	lxc_container_put(c);
>  
>  	/* XXX TODO load_config needs to clear out any old config first */
> -	if ((c = lxc_container_new(MYNAME)) == NULL) {
> +	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
>  		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
>  		ret = 1;
>  		goto out;
> diff --git a/src/tests/getkeys.c b/src/tests/getkeys.c
> index 9bb5593..bab6883 100644
> --- a/src/tests/getkeys.c
> +++ b/src/tests/getkeys.c
> @@ -35,7 +35,7 @@ int main(int argc, char *argv[])
>  	int len, ret;
>  	char v3[2048];
>  
> -	if ((c = lxc_container_new(MYNAME)) == NULL) {
> +	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
>  		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
>  		ret = 1;
>  		goto out;
> diff --git a/src/tests/lxcpath.c b/src/tests/lxcpath.c
> new file mode 100644
> index 0000000..8d8ad9c
> --- /dev/null
> +++ b/src/tests/lxcpath.c
> @@ -0,0 +1,85 @@
> +/* liblxcapi
> + *
> + * Copyright © 2012 Serge Hallyn <serge.hallyn at ubuntu.com>.
> + * Copyright © 2012 Canonical Ltd.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2, as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + *
> + * You should have received a copy of the GNU General Public License along
> + * with this program; if not, write to the Free Software Foundation, Inc.,
> + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
> + */
> +#include "../lxc/lxccontainer.h"
> +
> +#include <unistd.h>
> +#include <signal.h>
> +#include <stdio.h>
> +#include <sys/types.h>
> +#include <sys/wait.h>
> +#include <stdlib.h>
> +#include <errno.h>
> +
> +#define MYNAME "lxctest1"
> +
> +#define TSTERR(x) do { \
> +	fprintf(stderr, "%d: %s", __LINE__, x); \
> +} while (0)
> +
> +int main()
> +{
> +	struct lxc_container *c;
> +	const char *p1, *p2;
> +	int retval = -1;
> +
> +	c = lxc_container_new(MYNAME, NULL);
> +	if (!c) {
> +		TSTERR("create using default path");
> +		goto err;
> +	}
> +	p1 = c->get_config_path(c);
> +	p2 = c->config_file_name(c);
> +	if (!p1 || !p2 || strncmp(p1, p2, strlen(p1))) {
> +		TSTERR("Bad result for path names");
> +		goto err;
> +	}
> +
> +#define CPATH "/boo"
> +#define FPATH "/boo/lxctest1/config"
> +	if (!c->set_config_path(c, "/boo")) {
> +		TSTERR("Error setting custom path");
> +		goto err;
> +	}
> +	p1 = c->get_config_path(c);
> +	p2 = c->config_file_name(c);
> +	if (strcmp(p1, CPATH) || strcmp(p2, FPATH)) {
> +		TSTERR("Bad result for path names after set_config_path()");
> +		goto err;
> +	}
> +	lxc_container_put(c);
> +
> +	c = lxc_container_new(MYNAME, CPATH);
> +	if (!c) {
> +		TSTERR("create using custom path");
> +		goto err;
> +	}
> +
> +	p1 = c->get_config_path(c);
> +	p2 = c->config_file_name(c);
> +	if (strcmp(p1, CPATH) || strcmp(p2, FPATH)) {
> +		TSTERR("Bad result for path names after create with custom path");
> +		goto err;
> +	}
> +
> +	retval = 0;
> +
> +err:
> +	lxc_container_put(c);
> +	return retval;
> +}
> diff --git a/src/tests/saveconfig.c b/src/tests/saveconfig.c
> index bbaea19..fa84e32 100644
> --- a/src/tests/saveconfig.c
> +++ b/src/tests/saveconfig.c
> @@ -65,7 +65,7 @@ int main(int argc, char *argv[])
>  	struct lxc_container *c;
>  	int ret = 1;
>  
> -	if ((c = lxc_container_new(MYNAME)) == NULL) {
> +	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
>  		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
>  		ret = 1;
>  		goto out;
> diff --git a/src/tests/shutdowntest.c b/src/tests/shutdowntest.c
> index 9ad8a65..a1a84e8 100644
> --- a/src/tests/shutdowntest.c
> +++ b/src/tests/shutdowntest.c
> @@ -34,7 +34,7 @@ int main(int argc, char *argv[])
>  	struct lxc_container *c;
>  	int ret = 1;
>  
> -	if ((c = lxc_container_new(MYNAME)) == NULL) {
> +	if ((c = lxc_container_new(MYNAME, NULL)) == NULL) {
>  		fprintf(stderr, "%d: error opening lxc_container %s\n", __LINE__, MYNAME);
>  		ret = 1;
>  		goto out;
> diff --git a/src/tests/startone.c b/src/tests/startone.c
> index f76ed1e..1eb3e99 100644
> --- a/src/tests/startone.c
> +++ b/src/tests/startone.c
> @@ -103,7 +103,7 @@ int main(int argc, char *argv[])
>  
>  	ret = 1;
>  	/* test a real container */
> -	c = lxc_container_new(MYNAME);
> +	c = lxc_container_new(MYNAME, NULL);
>  	if (!c) {
>  		fprintf(stderr, "%d: error creating lxc_container %s\n", __LINE__, MYNAME);
>  		ret = 1;
> 


-- 
Stéphane Graber
Ubuntu developer
http://www.ubuntu.com

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 901 bytes
Desc: OpenPGP digital signature
URL: <http://lists.linuxcontainers.org/pipermail/lxc-devel/attachments/20130210/9fbe3c2d/attachment.pgp>


More information about the lxc-devel mailing list